ACL recovery time question on flex of knee.?

I had ACL replacement five weeks ago and am on third week of PT. I also had a complete tear of the MCL and ruptured lat meniscus. My concern is that it still take every thing I have to get a 90 degree bend. I have been doing the exercises and have a bike I am using at home. They are talking about having to go back to dr to have them "break" the scar tissue to get it to start bending. I am scared something is wrong. Should I be?